This invention relates to aliphatic diisocyanate compositions suitable in the preparation of polyurethane elastomers, especially of polyurethane coatings that can be moisture cured.
Use of certain aliphatic diisocyanates in the preparation of polyurethane elastomers is well known. Such elastomers can be made substantially colorless and transparent and thus are particularly suitable in coatings when it is desired to protect a decorative surface, such as a flooring or stained wood. Compared with aromatic diisocyanates, aliphatic diisocyanates have a shortcoming of being less reactive, so that curing of aliphatic diisocyanate-base prepolymers with certain curing agents, such as polyols or moisture, requires impractically long times. Moisture curing is a particularly desirable technique for polyurethane coatings. Accordingly, methods for decreasing the time to tack-free condition (hereinafter, tack-free time) have been sought by the industry.